The A.J.M. 9 is a futuristic auto-pistol that fires in full auto or burst. It has a built-in suppressor and laser tracker rounds, which makes it a quiet close-range sprayer.
It suits close-range fights where you want to stay quiet. The built-in suppressor means you can spray down a guard without fitting a mod. Its description calls it short-range and spray-and-pray, so do not expect precision.
It only takes armor-piercing rounds, which is fine against FND troops in helmets and vests. It has no mod sockets listed, so what you get is what you use.
.44 Magnum
The .44 Magnum is a six-shot revolver-style pistol that hits hard for a sidearm. Its two unique versions, Magnum, P.D. and The Big Dog, give you a quick-draw backup with real stopping power at short to mid range.
1911
The 1911 is a rare semi-automatic pistol in Far Cry 6, and one of the best all-round sidearms you can find. You unlock it through the And The Beat Goes On... treasure hunt, and it is Vaas's starting weapon in the Vaas: Insanity DLC.
57 USG
The 57 USG, sold as The Diplomat, is a high-capacity pistol from the Far Cry 6 online store. Its 20-round magazine and full set of mod sockets make it a flexible sidearm if you own it.
6P13 Auto
The 6P13 Auto is a fully automatic machine pistol with a 40-round drum. It sprays fast at close range, and its unique versions come from Los Bandidos operations and two insurgencies.